unnecessary escapes fixes (#50178) * unnecessary escapes fixes * replace some strings with raw strings * update regexp * address review comments

diff --git a/packages/flutter_tools/lib/src/android/gradle.dart b/packages/flutter_tools/lib/src/android/gradle.dart
index 9d386d5..b48306e 100644
--- a/packages/flutter_tools/lib/src/android/gradle.dart
+++ b/packages/flutter_tools/lib/src/android/gradle.dart

@@ -642,7 +642,7 @@
 
   for (final String buildMode in buildModes) {
     globals.printStatus('''
-      ${buildMode}Implementation \'$androidPackage:flutter_$buildMode:$buildNumber\'''');
+      ${buildMode}Implementation '$androidPackage:flutter_$buildMode:$buildNumber\'''');
   }
 
   globals.printStatus('''

diff --git a/packages/flutter_tools/lib/src/android/gradle_utils.dart b/packages/flutter_tools/lib/src/android/gradle_utils.dart
index 3a192fc..491fd12 100644
--- a/packages/flutter_tools/lib/src/android/gradle_utils.dart
+++ b/packages/flutter_tools/lib/src/android/gradle_utils.dart

@@ -128,7 +128,7 @@
 }
 const String _defaultGradleVersion = '5.6.2';
 
-final RegExp _androidPluginRegExp = RegExp('com\.android\.tools\.build\:gradle\:(\\d+\.\\d+\.\\d+\)');
+final RegExp _androidPluginRegExp = RegExp(r'com\.android\.tools\.build:gradle:\(\d+\.\d+\.\d+\)');
 
 /// Returns the Gradle version that the current Android plugin depends on when found,
 /// otherwise it returns a default version.

diff --git a/packages/flutter_tools/lib/src/base/utils.dart b/packages/flutter_tools/lib/src/base/utils.dart
index 8e60b51..a05e211 100644
--- a/packages/flutter_tools/lib/src/base/utils.dart
+++ b/packages/flutter_tools/lib/src/base/utils.dart

@@ -350,7 +350,7 @@
   // reconstitute the original string. This is useful for manipulating "visible"
   // characters in the presence of ANSI control codes.
   List<_AnsiRun> splitWithCodes(String input) {
-    final RegExp characterOrCode = RegExp('(\u001b\[[0-9;]*m|.)', multiLine: true);
+    final RegExp characterOrCode = RegExp('(\u001b\\[[0-9;]*m|.)', multiLine: true);
     List<_AnsiRun> result = <_AnsiRun>[];
     final StringBuffer current = StringBuffer();
     for (final Match match in characterOrCode.allMatches(input)) {

diff --git a/packages/flutter_tools/lib/src/fuchsia/fuchsia_device.dart b/packages/flutter_tools/lib/src/fuchsia/fuchsia_device.dart
index 937027f..1b37082 100644
--- a/packages/flutter_tools/lib/src/fuchsia/fuchsia_device.dart
+++ b/packages/flutter_tools/lib/src/fuchsia/fuchsia_device.dart

@@ -82,7 +82,7 @@
     // the correct fuchsia module.
     final RegExp matchRegExp = _app == null
         ? _flutterLogOutput
-        : RegExp('INFO: ${_app.name}(\.cmx)?\\(flutter\\): ');
+        : RegExp('INFO: ${_app.name}(\\.cmx)?\\(flutter\\): ');
     return Stream<String>.eventTransformed(
       lines,
       (EventSink<String> output) => _FuchsiaLogSink(output, matchRegExp, startTime),

diff --git a/packages/flutter_tools/lib/src/project.dart b/packages/flutter_tools/lib/src/project.dart
index 30cec47..2d01fcc 100644
--- a/packages/flutter_tools/lib/src/project.dart
+++ b/packages/flutter_tools/lib/src/project.dart

@@ -603,7 +603,7 @@
   String get pluginConfigKey => AndroidPlugin.kConfigKey;
 
   static final RegExp _applicationIdPattern = RegExp('^\\s*applicationId\\s+[\'"](.*)[\'"]\\s*\$');
-  static final RegExp _kotlinPluginPattern = RegExp('^\\s*apply plugin\:\\s+[\'"]kotlin-android[\'"]\\s*\$');
+  static final RegExp _kotlinPluginPattern = RegExp('^\\s*apply plugin\\:\\s+[\'"]kotlin-android[\'"]\\s*\$');
   static final RegExp _groupPattern = RegExp('^\\s*group\\s+[\'"](.*)[\'"]\\s*\$');
 
   /// The Gradle root directory of the Android host app. This is the directory

diff --git a/packages/flutter_tools/lib/src/protocol_discovery.dart b/packages/flutter_tools/lib/src/protocol_discovery.dart
index a13878e..acdb4d5 100644
--- a/packages/flutter_tools/lib/src/protocol_discovery.dart
+++ b/packages/flutter_tools/lib/src/protocol_discovery.dart

@@ -94,7 +94,7 @@
   }
 
   Match _getPatternMatch(String line) {
-    final RegExp r = RegExp('${RegExp.escape(serviceName)} listening on ((http|\/\/)[a-zA-Z0-9:/=_\\-\.\\[\\]]+)');
+    final RegExp r = RegExp(RegExp.escape(serviceName) + r' listening on ((http|//)[a-zA-Z0-9:/=_\-\.\[\]]+)');
     return r.firstMatch(line);
   }
 

diff --git a/packages/flutter_tools/lib/src/web/web_device.dart b/packages/flutter_tools/lib/src/web/web_device.dart
index 628a640..dffc866 100644
--- a/packages/flutter_tools/lib/src/web/web_device.dart
+++ b/packages/flutter_tools/lib/src/web/web_device.dart

@@ -193,7 +193,7 @@
 
 @visibleForTesting
 String parseVersionForWindows(String input) {
-  return input.split(RegExp('\w')).last;
+  return input.split(RegExp(r'\w')).last;
 }